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Seasoned astronomer but techy newbie - help!

suaveharv

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GazOC

GazOC

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Daz,

If you don't have enough back focus you need an extension, not enough front focus you need the Crayford. Try taking the lens out of a Barlow and putting that inbtween the focusser and the camera, you might be OK with that if it's back focus you're after.

By Binos need front focus, which is a much bigger pain!!!

Gaz

Gaz

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suaveharv

suaveharv

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Regarding your original question; what are your main interests - lunar, planets, or deep sky -

Steve :)

Thanks Steve.

I'm going to have to give the usual uninspiring answer "a bit of everything". I used to enjoy deep sky stuff with my Dob. In Cornwall, under a spectacular dark sky I once found some very faint galaxies and loved it. But living in the West Midlands I tended to neglect that side. I'd like to do some deep sky photography certainly. I wonder if I should go for a digital SLR? If the scope costs £520 then I can spare a few hundred for a camera. I'd budgeted £800. .

Thanks for all the responses. I'll get back to you more in depth you later this afternoon.

Cheers!

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FLO

FLO

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Suaveharv,

Written in haste:

If you smiled sweetly and used all your budget, I am sure you will get a dealer to let you have a Skymax 150 PRO...

http://tinyurl.com/cmxo4

... on the HEQ5 mount ...

http://tinyurl.com/dt4mq

... for £799. 

There are several posts regarding the 150 PRO and one mini-review - all praising it. 

I for one would be green with envy!

Steve :)

PS: I'll post a considered response on the digital SLR when able. 

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daz

daz

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Gaz

I think you may be right - it is front focus. I had a quick play this pm, and could not achieve focus no matter how far back I went. I want a crayford anyway because of the image-shift on the standard.

Really should check my facts before typing.....

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daz

daz

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Harv:

FYI - The HEQ5 mount is around 20lbs, the tripod another 10, the 2 counter weights are 5kgs's each, plus the scope (couldn't get that to balance on the scales!!)

So, you are looking at around 13kg's for the mount and tripod and 10 for the weights, then the scope. Like I said, not too heavy to put you off moving it, but heavy enough to be solid.

cheers

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OXO

OXO

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Thats the only gripe i have with the Skywatcher 200mm reflector the damn focusser is awful, this is a Nightmare when imaging at high Mag's esp Planets. I would think about getting the Crawford for it but my DIY skill's are shocking or at least when it comes to Astro Gear just too carefull if you get my meaning.

James :)

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suaveharv

suaveharv

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Suaveharv,

If you smiled sweetly and used all your budget, I am sure you will get a dealer to let you have a Skymax 150 PRO...

Thanks for that Steve.

The link you posted features a scope with a 6" mirror, and it's a Shimtt Cassigrain (sp???) - I thought they lost light gathering capacity because of the two mirrors. So is this a better scope than the 8" newtonian we were talking about?

I hadn't considered a S/C because I've read in books they compromised brightness for compactness.

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suaveharv

suaveharv

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James, thanks for the advice re. the camera.

I'd be happy to use my Olympus for a bit, until I got the hang of things. Why do you think it wouldn't be much good for deep sky? There is a function on it to set the shutter speed I'm sure.

BTW - I checked your photos and they are superb. I'd be most proud if I got some like that, loved the Saturn & Jupiter shots.

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FLO

FLO

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The link you posted features a scope with a 6" mirror, and it's a Shimtt Cassigrain (sp???) - I thought they lost light gathering capacity because of the two mirrors. So is this a better scope than the 8" newtonian we were talking about?

I hadn't considered a S/C because I've read in books they compromised brightness for compactness.

Suaveharv,

It is actually a Maksutov Cassegrain and yes, it is a Catadioptric.  A conventional Newtonian has two mirrors; Catadioptrics use three if we count the diagonal.  In theory at least, the diagonal will reduce some of the light though the loss is quite negligible.  (If this were a major concern there is always the Maksutov Newtonian). 

Advantages of a Maksutov Cassegrain are:

Incredibly sharp images that rival some of the best Refractors.

Convenient eyepiece position (thanks to the diagonal).

The slow focal ratio produces high magnification and allows the use of longer focal length eyepieces (better eye-relief). 

The front correcting lens, small central obstruction and lack of spider vanes produce high contrast. 

No need to re-collimate. 

Sealed tube so mirror stays clean and bright.

Disadvantages:

Expensive (though considerably cheaper than an equivalent refractor)

Slow f-ratios mean longer exposures and narrow field of coverage

They tend to have longer cool-down times.

A 6" Maksutov built as well as the Skymax 150-PRO should produce images better than the 8" reflector mentioned previously.  In particular, it will excel on solar, lunar, planets, globulars and other bright DSO such as the Ring and Dumbell Nebulas. 

IMHO I think it would be an excellent second scope because it is strong in the areas where your Newtonian is weak.  The two together would make a great combo.  (Like you, I have a 10" Dob and find my 4" Mak an almost perfect second scope but if an opportunity arose to upgrade it to the 6" Skymax - I'd do it in the blink of an eye. 

Hope that helps,

Steve :)

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FLO

FLO

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The only objects I can see a 8" SCT "beating" :) a 6" Mak on is the faint stuff...

I am sure you are right Gaz, the Schmidt shares some of the characteristics of a Mak though it has a larger central obstruction, so less contrast. 

But, we're comparing a 6" Mak with an 8" Newt ...

Steve :)

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suaveharv

suaveharv

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But, we're comparing a 6" Mak with an 8" Newt ...

Steve :)

And please carry on comparing, as I see it there's £180 difference in scope price (with the same mount), that's a big jump in price, so there should be a big jump (one giant leap?) in image quality.

Hmm. . and another hmmm.

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GazOC

GazOC

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Harv,

As an 'only' scope the Newt beats the Mak hands down IMHO, it's a better alround scope and will show great views of pretty much anything. The Mak is more of a planetary/double star/globs scope.

The other good news is that the Newt is cheaper!!

Gaz

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FLO

FLO

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IMHO, if you want to show galaxys as more than fuzzy shapes you need at least 10" aperture; 8" wont do it. 

So that leaves everything else: solar, lunar, planets, doubles, globulars and the brighter DSO.  And for that, aperture for aperture, the Mak wins.  So much so that if I had to choose, I would rather a 6" Mak than an 8" Newt. 

Steve :)

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